Certain refrigerator appliances include sealed systems for cooling chilled chambers of the refrigerator appliances. The sealed systems generally include a compressor that generates compressed refrigerant during operation of the sealed systems. The compressed refrigerant flows to an evaporator where heat exchange between the chilled chambers and the refrigerant cools the chilled chambers and food items located therein.
Recently, certain refrigerator appliances have included linear compressors for compressing refrigerant. Linear compressors generally include a piston and a driving coil. A voltage excitation induces a current within the driving coil that generates a force for sliding the piston forward and backward within a chamber. During motion of the piston within the chamber, the piston compresses refrigerant. Motion of the piston within the chamber is generally controlled such that the piston does not crash against another fixed component of the linear compressor during motion of the piston within the chamber. Such hard head crashing can damage various components of the linear compressor, such as the piston or an associated cylinder. While hard head crashing is preferably avoided, it can be difficult to accurately control a motor of the linear compressor to avoid hard head crashing. In addition, it can be difficult to accurately determine suction pressure and/or a discharge pressure of the linear compressor without costly pressure sensors.
Accordingly, a method for operating a linear compressor with features for determining a piston clearance without utilizing a position sensor would be useful. In addition, a method for operating a linear compressor with features for accurately determining a suction pressure and/or a discharge pressure of the linear compressor without costly pressure sensors would be useful.